Michaelmas Term, 1985. Dublin languishes in a fug of tobacco and poverty. Chucking in his factory job in Leeds and sneaking back without telling his ma, Declan joins the Trinity College creative writing class run, in theory, by his idol, the appalling genius Patrick Glynn. There are eight of them, "a shower of messers" all in awe of the great Glynn, all vying for his erratic approval. Declan, narrating, tells us how their year wears on. Much Guinness is drunk, much whiskey. Souls are bared, hearts are broken. Novels are begun, savaged, abandoned. The weakest fall by the way. Declan persists, along with a close-knit coven of women. It rains. Sometimes it's very cold. Gulls scream over the Liffey.

And that's about it, really. All Summer and Tenderwire, Claire Kilroy's first two novels, were thrillers, whatever else they were: driven by plot, by mysteries to be solved, treasures to be won. Anyone coming to All Names Have Been Changed in the hope of something similar may be nonplussed. It seems perhaps a shadow novel in Kilroy's career: an obligatory plunge back into her past, both personal (born in Dublin in 1973, she studied creative writing at Trinity in 1999) and artistically, as an inheritor of the mantle of the Irish literary tradition; and a thick, smothering sort of mantle it seems to be.

Every chapter title is a quotation from Irish literature or song, from Maria Edgeworth to John Banville, from "Molly Malone" to the Pogues, so we know what a crowd Kilroy feels craning over her shoulders. The story itself isn't 14 pages old before Joyce and Beckett show up, with Wilde close behind. When he does finally materialise, PJ Glynn is not so much Godot as O'God: the biggest, fattest, most arrogant, truculent, lachrymose, lecherous, bibulous, cowardly bully ever to waltz the Hibernian muse through the vomit and broken glass of Nighttown.

Kilroy herself has said writing is "like wandering around in the room in the dark", but as a former editor of TV drama she does bring certain skills to bear on the things she bumps into. Scenes begin in the middle (prescribed TV practice). Only later, sometimes after you've stopped wondering, does Declan let slip what's actually happened. It's characterisation, in a way, Declan being the sort of yearning onlooker who understands nothing, to whom nobody ever tells anything. It's also suspense, of a kind. Clarity postponed gains the force of revelation.

In any case, this is a book about emotions rather than events. However grim, its drama is there only to articulate the flow of sensibility, the endless poetic filtering of significance out of circumstance. Where all the action is involuntary, reactive or obsessive, plot is surely hard to contrive. Instead, Kilroy does choreography. Characters adopt attitudes, exchanging roles and moods as they slither dreamily up and down emotional arcs. Everyone clarifies gradually as the book progresses, emerging from the gloom as individual talents, each shrouded in their own private hell.

Kilroy's charting of the inner turmoil of the introvert lad who falls in love only to bollocks it all up is alarmingly perfect. And her best chapter, in which Declan strikes up a perilous acquaintance with Giz, the delinquent drug dealer downstairs, should be cut out and pinned up in creative writing classes throughout the land. Perhaps now she's sluiced Dublin out of her system we may look to be properly astonished by Claire Kilroy.

• Colin Greenland's Finding Helen is published by Black Swan. To order All Names Have Been Changed for £11.99 with free UK p&p call Guardian book service on 0330 333 6846 or go to theguardian.com/bookshop